1. Technical Field of the Invention
The present invention relates to an assembly of a case and electronic components, and to a combination of the assembly and external connectors.
2. Description of the Related Art
Conventionally, as shown in FIG. 30, there is known an assembly 90 that includes an electronic component 96, a bus bar 92 connected to the electronic component 96, and a case 91 that receives therein both the electronic component 96 and the bus bar 92. The assembly 90 is configured so as to allow the bus bar 92 to be connected with a terminal 95a of an external connector 95 by tightening a bolt 93 within the case 91 (see, for example, Japanese Patent Application Publication No. 2009-219284).
More specifically, the case 91 has formed therein both an opening 94 through which the bolt 93 is to be positioned inside the case 91 and an opening 97 through which the terminal 95a of the external connector 95 is to be inserted into the case 91. The opening directions (or facing directions) of the openings 94 and 97 are perpendicular to each other. In addition, the bus bar 92 has a through-hole 92a formed therein, while the external connector 95 has a nut 95b embedded therein.
In connecting the terminal 95a of the external connector 95 to the bus bar 92, the terminal 95a is first inserted into the case 91 through the opening 97, thereby bringing the nut 95b embedded in the external connector 95 into alignment with the through-hole 92a of the bus bar 92. Then, the bolt 93 is placed inside the case 91 through the opening 94, and tightened into the nut 95b through the through-hole 92a of the bus bar 92. Consequently, the bus bar 92 and the terminal 95a of the external connector 95 are fastened together by the engagement between the bolt 93 and the nut 95b. 
Moreover, the external connector 95 includes a resin-made body portion 95d and a connection portion 95c for making connection with an external device (not shown). The connection portion 95c has formed therein an internal space to which an end portion 95e of the terminal 95a is exposed. The end portion 95e is to be connected to an electric wire (not shown) extending from the external device, thereby electrically connecting the electric component 96 to the external device.
However, with the above configuration of the conventional assembly 90, during the connecting of the terminal 95a of the external connector 95 to the bus bar 92, the bolt 93 may be accidentally dropped into the case 91. In this case, if the bolt 93 drops down to a bottom portion 91a of the case 91, it will be difficult to take out the bolt 93.
In addition, it may be possible to take out the bolt 93 from the case 91 by turning the case 91 upside down and thereby causing the bolt 93 to fall out through the opening 94 of the case 91. However, this process is time-consuming, thus lowering the productivity. Moreover, during this process, the bolt 93 may collide with and thereby damage the electronic component 96.